Do we normally consider recorded music to be theft from musicians who would have been paid to play music live if we never allowed (or invented) recorded music?

Normally this isn't the case for any technology except for the time it first comes around. AI is only different to use for two reasons. First, it is in our time. Second, it seems to be faster than any of the options before, so the shock is harder.

But in general, this is a website of people writing code. How many on here study how a person solves a problem and then trains the ultimate chimpanzee to do (at least part of) their job? Is building computer programs that automate what others did manually theft?

Consider the origin of the word "computer" itself, a mass theft of jobs that would have employed the whole world many many times over.